Podcast Beta
Questions and Answers
What is electricity?
The invisible energy which constitutes flow of electrons in a closed circuit to do work.
What are the practical applications of electricity? (Select all that apply)
What happens to a body if electrons are removed from it?
It attains a positive charge.
What is the practical unit of charge?
Signup and view all the answers
What is electrical potential?
Signup and view all the answers
What is the unit of electric current?
Signup and view all the answers
What is Ohm's Law?
Signup and view all the answers
The formula for Ohm's Law is V = _____.
Signup and view all the answers
What is electromotive force (EMF)?
Signup and view all the answers
Ohm's Law is not applicable to which type of networks?
Signup and view all the answers
Study Notes
Electricity
- The flow of electrons in a closed circuit that allows work to be done.
- Plays a significant role in daily life for lighting, heating, cooling, entertainment (TV and radio), transportation, and calculations.
- Every matter is electrical in nature due to the presence of charged particles like electrons and protons.
- A body is typically neutral as it contains an equal number of protons and electrons.
- If electrons are removed from a body, it becomes positively charged due to an electron deficit.
- If electrons are supplied to a body, it becomes negatively charged due to an excess of electrons.
- The unit of charge is the coulomb (C).
- One Coulomb is the charge on 6.28 x 1018 electrons.
Free Electrons
- Electrons loosely attached to the nucleus of an atom, able to move when external energy is applied.
Electrical Potential
- The capacity of a charged body to perform work.
- Measured in volts (V) or joules per coulomb (J/C).
- A body has an electrical potential of 1 Volt if 1 Joule of work is done to charge the body to 1 Coulomb.
Potential Difference
- The difference in electrical potential between two charged bodies.
- Measured in volts (V).
Electric Current
- The continuous flow of electrons in an electric circuit, driven by an applied potential difference.
- The rate of flow of electrons, or charge flowing per second.
- Calculated using the formula: I = Q / t, where:
- I = current (Amperes)
- Q = charge (Coulombs)
- t = time (seconds)
Electromotive Force (EMF)
- The force that causes an electric current to flow in a circuit.
- Represented as energy, not a physical force.
- The amount of energy provided by the source to each Coulomb of charge.
Potential Difference
- The amount of energy used by one Coulomb of charge when moving from one point to another in a circuit.
Ohm's Law
- States that the current through a conductor is directly proportional to the applied voltage across it, assuming constant physical conditions like temperature.
- The proportionality constant is known as the resistance 'R' of the conductor.
- Measured in ohms (Ω).
- Mathematically represented by: R = V / I
- The voltage drop across a resistor is calculated as V = IR, meaning the potential difference across the resistor is equal to the current flowing through it multiplied by the resistance.
Limitations of Ohm's Law
- Not applicable for unilateral networks (e.g., diodes, transistors) that allow current flow in only one direction.
- Not applicable to non-linear networks, where the relationship between voltage and current is not linear.
Studying That Suits You
Use AI to generate personalized quizzes and flashcards to suit your learning preferences.
Related Documents
Description
Test your knowledge about the fundamentals of electricity, including the behavior of electrons, electrical potential, and the significance of electrical charge in daily life. This quiz covers essential concepts related to circuits, free electrons, and measurements used in the field of electricity.
